HUNDREDS of school dinner ladies and cleaners in North Wales are being threatened with the sack in a row over pay.

The move comes after the working week for dinner ladies was cut to 37 hours - raising costs and plunging the service into the red.

Among the options being considered by Wrexham council are increasing meal prices and sacking up to 500 staff to re-employ them on new contracts. The row follows a similar disagreement involving dinner ladies in Denbighshire.

The GMB, which represents 260 of the employees, last night warned workers could be balloted for industrial action over the plans which could see some lose up to #700 in wages.

GMB leader Dave Cliff said last night: "I find it incredible that the poorest-paid council staff could be treated in this way."

He added: "Basically what the council is saying is they would terminate the contracts for all the staff and impose new contracts that are even worse."

The row comes after the GMB discovered staff were not being paid according to a four-year-old agreement.

They were working 39 hours, when they should have been on a 37-hour week, Mr Cliff said.

The union prepared a case for an Employment Tribunal.

"But before the tribunal, the council accepted this was wrong and we won a substantial amount of back pay," he said.

"Now the council wants to claw that money back through new contracts."

The staff are also being asked to accept the scrapping of an agreement over a half-pay retainer during school holidays and pro-rata holidays, which could mean them losing #500-#700 a year.

Mr Cliff said most of the staff were earning #5.14 to #5.32 an hour.

In a letter to the GMB, Wynford Thomas, Wrexham council chief strategic service officer, warned the council could not support the cost of the 37-hour week.

"The proposals are a complete package of proposals and if there is no agreement with the trade unions, then I shall include in my report to the executive board the dismissal of catering and cleaning staff and re-engagement on new terms and conditions."

Wrexham Independent AM John Marek said: "I find it beyond belief that a Labour-led council would first of all be underpaying the lowest-paid people they employ and then threaten them with even lower wages."

Neighbouring Denbighshire council is still involved in a dispute with its school cooks.

The authority has refused to continue to pay a stand-by allowance for the summer holidays in addition to recent pay increases, so the cooks have lodged appeals to the Employment Tribunal.